Need some help with bumpsteer
#1
Newbie
Thread Starter
Join Date: May 2010
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1996
Model: Cherokee
Engine: 4.0L High Output
Need some help with bumpsteer
I recently installed a Rubicon Express 3.5" SuperFlex on my 96 Jeep Cherokee. I have the Serious Offroad UTK steering linkage with a RE Steering Stabilizer. Going relatively slow 30-50 the steering is fine. However, when I get up to about 55+ any bump I hit I have to fight the steering wheel. I was wondering if you could tell if I needed a drop pitman arm or not. Looking at what I have been able to find on the forums it look like it might be able to help, but I just wanted to confirm it first. I measured the overall height that I gained from top of axle to frame with my lift and it comes out to be 4" total lift in front and 6" total lift in back (I added a 2" shackle in the rear). Any help would be greatly appreciated.
#2
Senior Member
Join Date: Jul 2009
Location: Utah
Posts: 735
Likes: 0
Received 1 Like
on
1 Post
Year: 1999
Model: Cherokee
Engine: I6 4.0L
Bump steer is usually fixed by addressing your track bar angle in relation to your drag link angle. They need to be parallel to each other. At least as close as possible. Are you using the stock track bar bracket? A drop bracket from RE may solve your problem.
#4
Newbie
Thread Starter
Join Date: May 2010
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1996
Model: Cherokee
Engine: 4.0L High Output
I am using a RE adjustable track bar, I do not have a drop bracket for it.
#6
Newbie
Thread Starter
Join Date: May 2010
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1996
Model: Cherokee
Engine: 4.0L High Output
It tries to drift in to the other lane when driving and is difficult to control when hitting bumps. On smooth roads it wobbles but nothing overly violent. However I do have a steering stabilizer so I am curious what all that is hiding.
Trending Topics
#8
Newbie
Thread Starter
Join Date: May 2010
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1996
Model: Cherokee
Engine: 4.0L High Output
I have not checked my ball joints as of recently, they did not look like they were in very bad condition when I installed the lift and had the axle off. I think I will look more into the drop bracket for the track bar. Thanks for all of the help with this! I love the Steering Linkage set up that I got from Serious!
#9
Senior Member
Join Date: Jul 2009
Location: Utah
Posts: 735
Likes: 0
Received 1 Like
on
1 Post
Year: 1999
Model: Cherokee
Engine: I6 4.0L
Yeah my guess is a drop pitman would make issues worse. IIRC RE also makes a uni body brace that integrates into the drop bracket. I would reccommend that as well if it's in the budget.
Best of luck!
Best of luck!
#10
Member
Join Date: Apr 2014
Location: Sioux City, IA
Posts: 217
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1994
Model: Cherokee
Engine: 4.6L Stroker
Wait guys hold on. Wheres the logic here, this has nothing to do with his angles for the trackbar to draglink. Everything is fine on the steering aspect. its pretty darn close when you line it up.
You guys are sending this guy down the wrong path after a bunny that doesn't exist in that hole.
I had the same issue as he did right after I put my serious steering on, ended up finding out my pinion angle was the issue. Fixed that and bumpsteer went away.
Now going over this multiple times, my mind goes, pinion angle and also did you get the alignment done? whens the last time you had your tires balanced? As long as ball joints are good and as long as you get all the fundamentals done the steering should be fixed.
You guys are sending this guy down the wrong path after a bunny that doesn't exist in that hole.
I had the same issue as he did right after I put my serious steering on, ended up finding out my pinion angle was the issue. Fixed that and bumpsteer went away.
Now going over this multiple times, my mind goes, pinion angle and also did you get the alignment done? whens the last time you had your tires balanced? As long as ball joints are good and as long as you get all the fundamentals done the steering should be fixed.
Last edited by Codenamefa; 09-18-2014 at 01:48 PM. Reason: Second thought
#11
Senior Member
Join Date: Jun 2011
Location: Florida
Posts: 759
Likes: 0
Received 2 Likes
on
2 Posts
Year: 1999
Model: Cherokee
Engine: 4.0
Wait guys hold on. Wheres the logic here, this has nothing to do with his angles for the trackbar to draglink. Everything is fine on the steering aspect. its pretty darn close when you line it up.
You guys are sending this guy down the wrong path after a bunny that doesn't exist in that hole.
I had the same issue as he did right after I put my serious steering on, ended up finding out my pinion angle was the issue. Fixed that and bumpsteer went away.
Now going over this multiple times, my mind goes, pinion angle and also did you get the alignment done? whens the last time you had your tires balanced? As long as ball joints are good and as long as you get all the fundamentals done the steering should be fixed.
You guys are sending this guy down the wrong path after a bunny that doesn't exist in that hole.
I had the same issue as he did right after I put my serious steering on, ended up finding out my pinion angle was the issue. Fixed that and bumpsteer went away.
Now going over this multiple times, my mind goes, pinion angle and also did you get the alignment done? whens the last time you had your tires balanced? As long as ball joints are good and as long as you get all the fundamentals done the steering should be fixed.
#13
Member
Join Date: Apr 2014
Location: Sioux City, IA
Posts: 217
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1994
Model: Cherokee
Engine: 4.6L Stroker
The caster needs to be set properly. I based mine off this chart and got a pretty smooth setup from it.
http://go.jeep-xj.info/HowtoAlignment.htm
You are running a 3.5 Rubicon SuperFlex setup so you should basically think of it as 4" lift for now till the spings sag a bit. So basically 5.5-6.0 degrees should do in pinion angle for the caster.
http://go.jeep-xj.info/HowtoAlignment.htm
You are running a 3.5 Rubicon SuperFlex setup so you should basically think of it as 4" lift for now till the spings sag a bit. So basically 5.5-6.0 degrees should do in pinion angle for the caster.
#14
Senior Member
Join Date: Jun 2011
Location: Florida
Posts: 759
Likes: 0
Received 2 Likes
on
2 Posts
Year: 1999
Model: Cherokee
Engine: 4.0
Oh, I wasn't thinking caster when you said pinion angle. I have my caster within the factory spec. Still bump-steerish sensations.
Sidebar-Frank, I sent you an email if you have a second to check it.
Sidebar-Frank, I sent you an email if you have a second to check it.
#15
Member
Join Date: Apr 2014
Location: Sioux City, IA
Posts: 217
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1994
Model: Cherokee
Engine: 4.6L Stroker
Give it a shot anyways, you have adjustable control arms right? Get the pinion set a little differently and see how it rides, try 5.5 degrees and see how it goes. 3.5" Rubicon Express lifts are always a little taller. If you try it and it gets worse than I was wrong and you can just put it right back to where it was. I had to run 5 degrees on mine to get the bumpsteer to go away and it was originally set at 7 and had crazy bump steer. Even the alignment shop that I went to said that is where it should have been when I told them where I set it to, the shop does lifted vehicles atleast 5 times a day, they primarily work on lifted vehicles and offroad buggies. So its worth a shot to try and eliminate the bump steer. Also a thought, if you been playing with your steering adjustment screw on top of the steering gear box, probably was a bad idea, to tight and it will run all over the place and simulate bump steer.
Last edited by Codenamefa; 09-18-2014 at 10:52 PM.